The Law of Identity states "That every thing is the same with itself and different from another." A is A and not ~A.

This seems to assume a perspective which facilitates this conclusion (hence an axiom). If I were to chose a perspective P1 on A for which A = B yet find that for P2 ~= P1 A~=B, i.e. P1:A=B and P2:A~=B, I am drawn to conclude that there may be a P for which all objects are one.

This is sounding a lot like a dimensionality reduction problem; there is a thought-axis under which everything is connected, or indiscernible.

Continuing along this line of reasoning, I see no need for The Law of Non-contradiction and the Law of the excluded middle (I'm starting from here).

However, in real practical terms the law of identity (together with the other 2 axioms that follow it) is unquestionably useful/pragmatic. Yet I'm still confounded by these two ideas: On the one hand I (apparently) have to get by day-to-day and on the other I am drawn to the fleeting (post-human condition?) sensation that there is a unifying thought-axis but which however appealing is utterly useless.

  • This post has me at a dead end. I now understand the law of identity to be an axiom requiring no proof. the dead end comes from trying to reconcile two views which I think are possible, but I have no question.
    – val
    Jan 20 '14 at 19:06
  • Have you considered that maybe your puzzle is with the notion of what it means to have a definable negation operator over your logical system, rather than with identity as such?
    – Paul Ross
    Jan 20 '14 at 22:06
  • I had not explicitly - so thank you. This may sound naive but I assume there is no negation in that system. The notion of negation invites a dualist perspective that "contaminates" by introducing the idea of "edges".
    – val
    Jan 20 '14 at 23:13

But doesn't this assume a somewhat self-righteous perspective which facilitates this conclusion?

Yes, law of identity is an axiom, something that is asked to be considered true without proof. Generally, the only argument provided to support such a statement is its "self-evidence". But not all philosophies agree that identities exists. Probably the most famous saying expressing an other point of view is "No man ever steps in the same river twice", attributed to Heraclitus.

Continuing along this line of reasoning, what need is there for The Law of Non-contradiction and the Law of the excluded middle?

You will probably want to document on constructionism.

(Please try to put a question in your title and to use the description to specify your request.)


I might be reading something into your thoughts that you're not intending, so feel free to take this with as much or as little relevance to your enquiries as you wish.

It seems like something that might be a useful piece of conceptual technology for you would be the idea of Logical Intension. In analytical philosophy of language, we often draw a distinction between two senses in which a word, a naming or predicative phrase, or a sentence means something.

On one hand, we might have a direct notion of reference - that is, the thing to which a name refers. So if I mention "the tree in the courtyard", to say of this phrase that it has a reference is to say that there is something in the world (or to avoid metaphysical readings, we might say in my frame of reference) such that it is a tree, and that in using that naming phrase, I might be intending to specifically ascribe properties or descriptions to that thing.

Of course, not every sensible piece of language I might want to use has an obvious reference. Let's say for example that I want to talk about unicorns. Now unfortunately, there are no unicorns (as far as I'm aware; at least, there certainly aren't any unicorns in my frame of reference). But on the other hand, that doesn't mean that any instance of the phrase "unicorns are..." is without meaning. I can mention unicorns, confident that other people will understand that I mean to talk about creatures like spiral-horned horses, even in the absence of anything to function as a clear referential object of the term "this or that unicorn".

This other kind of meaning of a word, a kind of indirect, descriptional notion of meaning where we associate words or phrases with some kind of psychological event, construction procedure, experimental verification or falsification scheme etc. is called intensional meaning or just the intension (or sometimes sense, in the work of Gottlob Frege who is often credited with drawing the distinction in formal analytical theory), in contrast with the "extensional meaning" that we more commonly think of as just "the stuff that we're talking about". The idea is that we draw a distinction between the domain of things that the language is used to denote or talk about and the means of presentation of the things we want to talk about that language use signifies.

So to your particular problem then. Abstractly, we might reflect on what it means for something to be a proposition or an object of identity, and thus give it a generic name. Let's say A. A names something in the world, but we might say that there could be some other description of the same object that A refers to, but that has a distinct intension from A - let's call this B. So A and B are stipulated to refer to the same thing, but that have different intensions, as noted in one of them being A and the other being B.

Now! The statements of identity that A=A and A=B look to be very different statements. To say that A has the same reference as itself is in some sense uninteresting. It seems to be little more than an intuitive sense of what it means for a relation to be an identity relation - namely, that it matches objects on either side of the = symbol (this is a sense in which the axiom of identity can be read - as specifying that A=A is something of a prerequisite for some relation to be properly considered as a candidate "identity" relation. in different contexts, 'Identity' might have different additional connotations, though I'm staying clear of that for now). Yet to say that A and B, intensionally distinct descriptions, have the same reference as each other, might be quite interesting. That is, two different ways of presenting an object in some sense converge towards one another at the level of referential identity.

One popular example might be "Clark Kent" and "Superman". It's part of the mythos of the story of Superman that he takes on the persona of Clark Kent to disguise himself on Earth, so the two are the same on a direct referential level. But actually, finding out that Clark Kent is Superman is, to the people that know either Clark or Super independently, quite a big deal! Who knew that the mild mannered guy working in the news room actually turned out to be a superhero crime fighter, right?

Drawing a distinction between extensional and intensional meaning might help you puzzle through some of your thoughts about how perspectives and axiomatic identity relations might come into play here. How do we use our language, logic and conceptual technologies in making claims and assertions about a given frame of reference, and how do matters of good practice, convention, shared reasoning patterns or communication standards influence the ways in which we connect elements of our objective picture of the world together?

Because I think you're right in many ways - on an extensional level, axiomatic specification of what it takes for something to be an identity relation doesn't tell you everything that might be psychologically or computationally interesting about what kinds of things are identical. It might be that without enough of a background framework about what kinds of things we want to include as modelling assumptions, conceptual tools, community conventions etc. for intensional descriptions, distinctions that we think should be obvious and rational just can't be drawn.

And if we think that's okay, then what's the specific motivation of excluded middle or non-contradiction? If it's not prima-facie simply logical (in the classical Aristotlean sense) that there are referentially distinct things, or that all distinctions that we take to be logical occur strictly at the level of reference, then what does the idea of Negation amount to? Why should there be neat and clear distinctions between any given property and its lack, absence or exclusion?

I think there are interesting proposed answers to those questions at least in as much as mathematics, culture, psychology or social structures are the domain of logical enquiry, though their methodologies are very much distinct, and in many ways significant (and potentially dangerous) issues emerge when we try to think of any framework as a dominating philosophical paradigm. The question that might be worth thinking about as a prerequisite for making progress here is what, or perhaps even who, your philosophy is ultimately for, and then to have a look at how they progress in their investigations and model building.

  • thank you for your post. I would upvote you if I could ...life is tough at the bottom of the pile ;) . I need time to consider and look some of this stuff up (though you've made your posts very readable there is a lingo barrier to chug through). Further, I find it hard to keep things straight when one is trying to define things; I fall (or bifurcate?) into the "trap" of what it actually means to define something using language (i.e. how accurate can I really get and does that even make sense to ask). My best conclusion so far is that silence is in a sense the best way to explain some things.
    – val
    Jan 22 '14 at 17:11

I'm not sure I really understand what's at stake here, but it seems like you are driving for some big cosmic conclusion (all is one?) on the basis of some kind of Hegelian sounding logical considerations. You say,

there is a thought-axis under which everything is connected, or indiscernible.

That sounded wrong to me. I don't understand what a thought-axis is supposed to be, but more importantly "being connected" and "being indiscernible" are clearly two radically different concepts. Two things A and B are indiscernible when and only when every property of A's is also a property of B's and vice versa. I'm connected to lots of stuff--my computer with which I'm typing, the air which I'm breathing, etc. But I'm not indiscernible from anything but myself. Here's a property I have that the air I breathe doesn't--I'm a human being, and the air isn't. From this it follows that the air and I are distinct.

  • I don't think a conclusion is attainable for the same reason I wouldn't call an orange a circle ("hey, can you pass me a circle please?"); the words and the thoughts are too coarse. Philosophy (to me) thus becomes an exercise, with utilitarian outcomes in some cases. By "connectedness" I meant connections through levels of abstraction. If you agree that on some abstract plane two (so-called) disparate objects may share similar patterns the suggestion that they are connected may be reasonable. If they are connected then we were always talking about aspects of one thing. Too banal perhaps.
    – val
    Jan 21 '14 at 20:21

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